Powder-making



N. DE MAKAY POWDER-MAKING Nov. 28, 1961 2 Sheets-Sheet 1 Filed Dec. 28, 1956 INVENTOR Nicolas De Makafi pm QjA Z JWM ATTORNEY Nov. 28, 1961 Filed Dec. 28, 1956 N. DE MAKAY 3,010,149

POWDER-MAKING 2 Sheets-Sheet 2 INVENTOR N \colasDe Ma k pmg flms uwm ATTORNEY atent Patented Nov. 28, 1961 3,010,149 POWDER-MAKING Nicolas de Makay, 227 Av. Erasmo Braga, Rio de Janeiro, Brazil Filed Dec. 28, 1956, Ser. No. 631,161 Claims. (Cl. 18-12) This invention relates to apparatus for making powder and particularly to press structures for forming the powder into grains or similar forms.

In general, the powder is formed into thin sheets and discs are cut from the sheets by suitable apparatus, the discs are then stacked for transfer to the hydraulic press arrangement of the invention wherein the powder is formed into conventional powder grain such as rods, tubes or threads.

One of the objects of the invention is to prevent explosion of the powder in the press which would destroy the press and endanger the lives of the press operators. By relieving the press operators of the fear of danger their efficiency is increased.

It is a further object of the invention to minimize the danger of fire in the press.

A still further object of the invention is to provide means for evacuating the air from the press so as to eliminate air bubbles in the powder and thus make a more homogeneous powder having uniform burning properties.

In the special press concerned, many of the features of which are shown in applicants copending application, Serial No. 345,932, dated March 31, 1953, of which this application is a continuation-in-part, the press is located in one room and the operating personnel receiving the formed or extruded powder are located in a separate room, the rooms being connected by a closable aperture. The press has a hydraulic ram connected to a piston insertable into a die cylinder having a die at one end. Means are provided for tightly sealing the end of the die cylinder and the ram so no air can escape at that end of the die cylinder. The air is evacuated from the cylinder by any conventional means. The ram has a means tending to lift it from the die cylinder. The hydraulic circuit for the press operation is arranged so that electronic or similar safety devices will release hydraulic pressure on the ram upon the occurrence of fire, release of said pressure permitting the ram to be removed from the cylinder by the means tending to lift it. This will permit the powder to burn free instead of under confined conditions, the latter being destructive and dangerous. The electronic circuits of the press also serve to close the aperture between the press operating room and the room with the personnel in it. Among the advantages of the invention can be enumerated the virtual elimination of fire and explosions and consequent interruptions to operation. The invention is especially adapted to the manufacture of a rocket propellant where uniformity and quality must be high.

Other objects, advantages and features of this invention will become apparent from the following description and drawings which are merely exemplary.

In the drawings:

FIG. 1 is a fragmentary view, partly in section, of the hydraulic powder press of the invention; and

FIG. 2 is an enlarged view of the air locking means of the invention.

In FIG. 1 some of the parts of the hydraulic powder press are schematically illustrated. Hydraulic cylinder 1 may be suitably supported on the floor 2 of the press room 3. The rod 4 attached to ram 5 is connected with some suitable force applying means, such as a weight and lever or hydraulic mechanism normally exerting force in anupward direction, the force being less, however, than that on the top of ram 5 when hydraulic pressure is ex-.

erted thereon. Die 6 is removably held in the die cylinder 7, the discs of powder being seen at 8 in the powder or die cylinder 7.

Room 9 can be located below the press room 3, there being an aperture 10 connecting the two. In operating room 9, the extruded powder is fed over or through guide means 11 to the powder receiving means in the room, the personnel being in this room. Suitable press heating means can be utilized to maintain the press at from about 70 to C., care being taken to preheat the press and die.

Trap doors 12 are arranged so as to be normally in open position, but so that they will automatically close in the event of fire below die 6. Photocell means 13 can be connected to schematically shown control box 14. Control box 14 can be arranged to furnish an electric impulse or current through line 15 to the electric fuse or detonator 16. The electric fuse or detonator 16 controls a valve maintaining pipe 17 normally closed. When the detonator is actuated, the valve and pipe will be opened so as to release pressure from cylinder 1. Control box 14 also can be connected through lines 18 with the trip mechanisms 19 for door operating mechanisms 20. Fluid for operating the ram can be furnished through line 21 and control valve 22 to cylinder 1.

If a fire is detected by the photocell means 13, control circuits in control box 14 will cause a detonation of the fuse 16 so as to open vent line 17 which will permit a rapid reduction of pressure in cylinder 1, so that the upward force on 4 will pull the ram 5 upwardly and clear of the die cylinder 7. At the same time, a signal will be transmitted to the trip mechanisms 19 so as to cause the doors to close rapidly. Springs or other suitable means can be used to close the doors and one or more doors can be used.

Connected to the end of ram 5 adjacent die cylinder 7 is an air locking assembly shown generally in FIG. 1 at 23. This assembly, as shown in detail in FIG. 2, has a flanged annular ring 24 with an inner diameter larger than the outer diameter of the portion of ram 5 upon which it is mounted. An annular ring 25 is mounted in a groove 26 in ram 5. Ring 25 has a seat 27 on which is mounted an annular T-shaped ring 28. Ring 24 also has a seat contacting ring 28. Flanged annular ring 29 having handles 30 is threadingly mounted on ring 24 for movement relative thereto. Annular ring 31 is mounted beneath ring 29 for sliding movement into the recess between ring 24 and ram 5, said ring moving into only a portion of said recess. The remainder of the recess is filled with an airtight resilient packing material 32, so that upon movement of ring 29 toward ring 24, packing material 32 is forced against ring 24 and ram 5 providing an airtight seal therebetween.

Mounted on the bottom surface of ring 24 is a resilient airtight annular ring 33 which contacts die cylinder 7 i when the ram '5 is brought downwardly, thereby providing an airtight seal between ring 24 and die cylinder 7. Ring 24 is provided with an airpassage 34 connected through suitable hose connections 35 to switch 36 and to a vacuum pump (not shown).

After the ram has been brought to the position shown in FIG. 2, the vacuum pump is actuated evacuating the air from the die cylinder. Due to the fact that the ram 5 has an outside diameter smaller than the inside diameter of the die cylinder, as clearly seen in FIG. 2, any air which might leak around ring 25 when the ram is in the die cylinder will also be evacuated. The air line and connection to the vacuum pump could also connect directly to the interior of the die cylinder rather than through ring 24, as shown in FIG. 2. The evacuation of the air from the die cylinder helps preventfires I and also eliminates air bubbles in the extruded powder It is to be understood that details of construction I can be varied without departing from the spirit of the invention except as defined in the appended claims.

What is claimed is: 1. In an apparatus for extruding powder, the combination including a die cylinder for receiving said powder, a die adjacent one end of said cylinder, a ram enterable into said cylinder for forcing the powder through said die, means slidably mounted on said ram for sealing said ram relative to said cylinder prior to operative engagement of said ram relative to said cylinder, means for evacuating air from said cylinder, re-

tracting means for constantly urging the ram away from said cylinder, hydraulic means for urging said ram into said cylinder with sufiicient force to overcome the force exerted by said retracting means, normally closed pressure releasing means connected to said hydraulic means and fire detective means connected to said pressure releasing means to open said pressure releasing means in the event of fire so as to allow the ram to be withdrawn from the die cylinder responsive to'the retracting means urging the ram away from the die cylinder.

2. 'In an apparatus for extruding powder, the co bination including a die cylinder for receiving powder, said cylinder having a die adjacent one end thereof, a ram tor a piston enterable into said cylinder forcing the powder through said die, means slidably mounted on said ram for providing an airtight seal between said cylinder and said ram prior to operative engagement of said ram relative to said cylinder, means for evacuating air from the interior of the cylinder to remove air bubbles from the extruded powder, retracting means constantly urging the ram away from the cylinder, hydraulic means activating the ram with suflicient force to overcome the force exerted by said retracting means and to extrude powder through said die, normally closed pressure releasing means connected to said hydraulic means, and photosensitive means connected to said pressure releasing means for opening the same in the event of fire at said die so as to allow said Sam to be withdrawn from said die cylinder responsive to the means urging the ram away from the cylinder.

3. in an apparatus for extruding powder, the com- 1 bination including a die cylinder'for receiving said powder, said die cylinder being'located in a pressroom having an aperture through which formed powder passes, said cylinder having a die adjacent one end thereof, a

ram enterable into said cylinder for forcing the powder through said die, an assembly slidably mounted on said ram for providing an airtight [seal between said cylinder and said ram, means connected-to said assembly for evacuating air from the interior of said cylinder so that when saidpowder is extruded from said die it will be in the event of fire at said die so as to allow said ram to be withdrawn from said cylinder responsive. to the means urging said ram away from the cylinder and closing means for the aperture in the press room, said closing means being normally open but closable in response to the activation of said photosensitive means in the event of fire.

4. In an apparatus for extruding powder, the combination including a die cylinder for receiving said powder, said die cylinder being located in a press room having an aperture through :which formed powder passes, said cylinder having a die adjacent one end thereof, a

ram for a piston enterable into said cylinder for forc ing the powder through saidjdie, an assembly slidably v mounted on said ram for providing an airtight seal between said cylinder and said ram, said assembly including two annular members movable relative to each other, packing between said members and means for movingsaid members relative to each other so as to force said packing tightly against said ram in order to prevent the leakage of air around said'rarn, means connected tosaid assembly'for'evacuating air from the in-. ter-ior of said cylinder so that when said powder is extruded from said die it will be free of air bubbles, means urging said ram and piston away from the cylinder, hydraulic means activating said ram and piston so as to extrude the powder, explosive actuated means connected tosaid hydraulic means for releasing the same so that upon actuation the piston means will move out of said cylinder responsive to the means urging said ram and piston away from the cylinder, photosensitive means near the outlet of said die cylinder for actuating said explosive means in the event of the at said die, and

. closing "means for the aperture. in the press room, sm'd closing means being normally opened but closable in S. In 'anapparatus for extruding powder, the cornbination including adie' cylinder *for receiving powder,

free of air bubbles, means urging said r-arn'away firom' the cylinder, hydraulic means activating said ram to extrude' the powder, normally closed pressure releasing means connected to saidhydraulic means, photosensitive means for opening said pressure releasing means said die cylinder being located in a pressTroom having an aperture through which formed powder passes, said cylinder having a die adjacent one end thereof, a ram for a piston enterable into said cylinder forcing the powder through said die, means urging said ram and piston away from the cylinder, hydraulic means activating said ram to extrude powder, normally closed pressure releasing means connected to said j-hydraulic means, photosensitive means opening said pressurejreleasing means in the event of fire at saiddie so as to allow said ram to be withdrawn from said diecylinder responsive to the means urging-said ram and piston away from the cylinder, closing'means .for the aperture in the press room; said closing means being normally open butclosable in response to the operation of said potosensitive means in the event of fire.

' References Cited in the tile of this patent UNITED STATESPATENTS I V Duliee et al. Sept. 30, Q1919 ,2,325,119 Flowers July'27, 1943 2,335,307 Pendergrast Nov. 30, 1943" 2,443,586 Stuart 1 June 15, 1948 2,570,280 Rotiman oa -9,1951 

